(* M2BasicBlock.def converts a scope block into a list of basic blocks.

Copyright (C) 2001-2025 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Modula-2; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  *)

DEFINITION MODULE M2BasicBlock ;

(*
   Title      : M2BasicBlock
   Author     : Gaius Mulley
   Date       : 20/8/2003
   System     : GNU Modula-2
   Description: Converts a scope block into a list of basic blocks.
                The basic blocks are either converted back into quadruples
                or alternatively translated into GCC trees.
*)

FROM M2Scope IMPORT ScopeBlock ;


TYPE
   BasicBlock ;
   BasicBlockProc = PROCEDURE (BasicBlock) ;


(*
   InitBasicBlocks - converts a list of quadruples as defined by
                     scope blocks into a set of basic blocks.
                     All quadruples within this list which are not
                     reachable are removed.
*)

PROCEDURE InitBasicBlocks (sb: ScopeBlock) : BasicBlock ;


(*
   InitBasicBlocksFromRange - converts a list of quadruples as defined by
                              start..end.
                              All quadruples within this list which are not
                              reachable are removed.
*)

PROCEDURE InitBasicBlocksFromRange (ScopeSym: CARDINAL;
                                    start, end: CARDINAL) : BasicBlock ;


(*
   KillBasicBlocks - destroys the list of Basic Blocks and assigns bb to NIL.
*)

PROCEDURE KillBasicBlocks (VAR bb: BasicBlock) ;


(*
   FreeBasicBlocks - destroys the list of Basic Blocks.
*)

PROCEDURE FreeBasicBlocks (bb: BasicBlock) ;


(*
   ForeachBasicBlockDo - for each basic block call procedure, p.
*)

PROCEDURE ForeachBasicBlockDo (bb: BasicBlock; p: BasicBlockProc) ;


(*
   GetBasicBlockScope - return the scope associated with the basic block.
*)

PROCEDURE GetBasicBlockScope (bb: BasicBlock) : CARDINAL ;


(*
   GetBasicBlockStart - return the quad associated with the start of the basic block.
*)

PROCEDURE GetBasicBlockStart (bb: BasicBlock) : CARDINAL ;


(*
   GetBasicBlockEnd - return the quad associated with the end of the basic block.
*)

PROCEDURE GetBasicBlockEnd (bb: BasicBlock) : CARDINAL ;


(*
   IsBasicBlockFirst - return TRUE if this basic block is the first in the sequence.
*)

PROCEDURE IsBasicBlockFirst (bb: BasicBlock) : BOOLEAN ;


END M2BasicBlock.